One of the few fruits in my garden is passion fruit, Passiflora edulis "Frederick". I posted a photo of the very first fruit off my vine in this week's Harvest Monday post. Thomas commented that he was curious to see what the plant looks like and I wasn't sure if I had posted a photo of the plant, other than the beautiful flowers. So, I thought I would write a post about growing passion fruit. This is a good refresher for me!
Here's a photo of the beautiful passion flower.
The name of the plant comes from the fact that colonizing Spanish missionaries used the flower to explain the crucifixion (passion) of Jesus to converts. The three styles represent the nails used to put him on the cross. The anthers represent his wounds. The filaments symbolize his crown of thorns. And the 5 petals and 5 sepals represent his apostles (not including Peter and Judas).
There are hundreds of species of Passiflora, both fruiting and ornamental. Most of the plants are native to the tropics and will not grow outside in temperate zones. This post is only about growing purple fruited Passiflora edulis, which is subtropical and can grow and fruit as far north as the San Francisco bay area in California. In my zone 9 climate the vine will grow in a spot that is not subject to too much frost. The plants will tolerate brief periods of cold down to the high 20F's and may die to the ground if we get a freeze. They will generally grow back after being knocked down by a freeze.
Here's a photo of some fruits hanging on the vine now. The remind me of dangling earrings.
The fruits start out green and turn purple as they ripen. They can be picked when they turn completely purple, but the best way to harvest passion fruits is to let them fall from the vine. The fruits should be further ripened indoors at room temperature until the skins start to shrivel. After that they can be stored at about 50F for 2 to 3 weeks.
Here's a shot of the upper part of the plant growing on the fence that surrounds my vegetable garden.
In colder climates like mine (cold for passion vines!) the plants should be grown in full sun in a spot that is protected from wind and frost. Against a wall would be an ideal spot. Overhead protection would help to prevent frost damage. You can see that I have neither protective measure here, but the nearby oak trees do provide quite a bit of shelter. This corner of the garden faces south and is the least frosty area in the vegetable garden. The plant made it through a couple of heavy frosts last winter, just losing some leaves. In areas that are hotter than my cool coastal climate, the vines would do better in partial shade.
In my cool winter climate the plants should be pruned in the spring. Prune after the harvest in warm winter climates. The plants can grow 15 to 20 feet a year when they are established and happy, so they need to be pruned to keep them in check. I doubt that my plant will ever be that vigorous, but I'll prune lightly next spring to promote new vigorous growth. The deer help with the pruning by eating anything that grows outside the fence and is within their reach!
Here's a shot of the whole plant. Rather scraggly when seen in its entirety.
The plants do quite well in large pots. It would probably do fine if I were to plant it in the ground but I'm sure I would lose it in no time flat to gophers. They will grow in most any type of soil so long as it is well drained and has a fairly neutral pH. Fertilize regularly with high potassium fertilizer such as 10-5-20.
Here's the second piece of ripe fruit and a few more ripening, and some of the seeds.
Passion vines can be propagated from seeds, cuttings, or by layering. I'm going to try growing some plants from seeds. These may not come true since "Frederick" is a cross between "Kahuna" and "Brazilian Golden" , but I think it will be interesting to give it a try. I've seen various recommendation for growing the plants from seed, but the most important things seem to be to use seeds freshly extracted from the fruit and scoring the hard seed coats. The seeds need warmth to germinate so I'll be putting them on heat mats under grow lights.
Now I'm going to finish slurping the pulp out of that fruit - yum!
Here's a couple of information packed websites I found about growing passion fruit: